Action support for Snapshots model

[solj]

We need to add Action entries to Snapshots to prevent this:

Failed to bind entry: Action googleearth
Handled 1 events in 0.000s
Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python2.5/threading.py", line 486, in __bootstrap_inner
    self.run()
  File "/usr/lib/python2.5/threading.py", line 446, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/root/bcfg2/Bcfg2/Server/Plugins/Snapshots.py", line 79, in load_snapshot
    self.statistics_from_old_stats(metadata, data)
  File "/root/bcfg2/Bcfg2/Server/Plugins/Snapshots.py", line 98, in statistics_from_old_stats
    + build_snap_ent(entry)
  File "/root/bcfg2/Bcfg2/Server/Plugins/Snapshots.py", line 34, in build_snap_ent
    datafields[entry.tag]])
KeyError: 'Action'

[solj]

Closing for now as DBStats is the way to go for reporting stuff.